SSG and VLAN routing

My network is comprised of 40ish HP Procurve switches with an SSG-550M at the front. The edge switches are procurve 2524s and procurve 2650s. I have 3 core switches (fiber distribution mostly), 2 of wich are HP Procurve 5304s, and an Extreme Summit x450a. I have 6 VLANs configured and currently VLAN routing is done on the extreme switch using switch policies for vlan security.

The Extreme switch, while is a monster of a switch, leaves much to be desired in terms of VLAN policy administration. Im thinking of moving my VLAN routing onto the SSG-550, wich is a MUCH easier solution for vlan policy management. Is this a bad idea, a good idea, or maybe?